Wednesday, 21 December 2016

As another year comes to an end, the results of the RSPB’s internal
competition to find the best passage wader site, The Golden Wellies, have just been announced. The rules are simple: monthly counts of waders
are recorded; they have to be ‘feet down’ (no fly-overs) on a managed
fresh/brackish scrape or flood (not tidal). The idea behind the competition is
also simple: you may not be interested in rare waders on your site but they
tend to indicate a well-managed site.A
well-managed site will attract many common breeding and passage birds, rare
birds will also tend to arrive at such sites. The better the feeding conditions,
the more likely they are to stay. Extra elements to the competition test good
wetland management throughout the year and also the accessibility of good birds
to weekend birders by having a ‘rare bird Saturday bonus’.

The Premier League champions are, yet again, Frampton Marsh. Frampton
recorded 34 species, narrowly pipping Titchwell (33) who were top of the League
for most of the year. The highlights of Frampton’s year included
Long-billed Dowitcher, Black-winged Stilt, Broad-billed, White-rumped and
Pectoral Sandpipers, as well as peak counts of 258 Curlew Sandpipers and 50
Little Stints. Titchwell could only
muster a feeble Great Knot, Pacific Golden Plover and a couple of Pec Sands. Frampton had an average monthly peak of 4,856
waders of 25.1 species, compared to Titchwell’s slightly higher Knot-fuelled
monthly average of 5,267 waders of 23.4 species.Minsmere’s much lower monthly average of 526
waders nether-the-less still maintained a monthly diversity of 24.0 species. If
only they could record a Temminck’s Stint! Snettisham records the most waders monthly –
an average peak of 39,300 birds, but only averaging 15.3 species a month.

The Golden Wellie also
includes a breeding wader productivity award – won this year by Burton Mere
Wetlands on the Dee Estuary.Middleton
Lakes (27 species), the Aire Valley (26) and the Ouse Washes (26 species) all again
demonstrate that well managed inland sites can compete with the coast in
terms of wader diversity if not numbers.A new entry this year, Wallasea, gained immediate promotion from League
1 with a notable 23 species – what will it get when the site is completed?In the north and west, Loch of Strathbeg,
Conwy and Belfast Lough all perform well given they struggle to record the
southern certainties of Avocet and LRP.

In all, 43 species of wader were recorded during the year, with a peak
monthly count of 111,719 birds being recorded across RSPB ‘wader scrapes’ in
September. Monthly peak counts included 399 Whimbrel in April, 22
Black-winged Stilts in May, 12 Red-necked Phalaropes in June, 228 Green
Sandpipers in July, 16,800 Black-tailed Godwits, 334 Ruff, 411 Curlew Sandpipers
and 123 Little Stints in August, and 3,151 Avocets and 40 Jack Snipe in
September.

Although the Golden Wellie has 48
competing sites across three leagues, the top performing 15 sites in 2016 were
as follows:

Tuesday, 22 November 2016

The fact that Lakenheath Fen RSPB reserve was a carrot field some 20
or so years ago is often repeated.The
detail that has gone into the design of the site and the management for key
species is less often appreciated.This
is no airy-fairy, lets see how it develops type of reserve, beloved of some
sections of the conservation community.This is a targeted and planned development that now delivers for
Bitterns, Cranes, Bearded Tits, Marsh Harriers, Water Voles, Otters and a range
of specialised wetland and Breck plants and invertebrates.

This week,
I attended the ecological review for the year and undertook the annual audit. There were a minimum of 5 booming Bitterns,
with at least 3 successful nests. We reviewed the results of the fish survey
throughout the reserve and discussed the habitat management. The detailed management undertaken for Bitterns that
has led to a remarkable recovery in the UK is well known, but perhaps the work
for Cranes less so. Cranes have also had
a good year at Lakenheath Fen with three chicks fledged from the 2 nesting pairs.But this is no chance event, rather the
result of considerable effort by site staff.

The case of
Cranes is an interesting one.Recently
released figures show a total of 48 pairs in the UK this year:a combination of 27 pairs of (mainly) wild
birds in 4 population centres and 21 pairs of the ongoing re-introduction
scheme in Somerset. At least 16 young were reared this year. The population in
the Fens is doing well, contributing 7 of these fledged youngsters, whilst the
Broads contributed 4 and Somerset just one.

There have
been several re-introduction schemes of various species of cranes around the
world.None have been totally successful.They have suffered from various problems such
as imprinting on humans, lack of migratory instinct, poor productivity and the cranes generally failing to think and act like wild cranes, particularly when it comes to
predators! The well publicised nesting attempts of some of the released birds where they clearly
fail to recognize good nesting habitat or exhibit typical crane behaviour is a
good example.Lets hope these issues can
be resolved.

So how has
Lakenheath become the UK crane powerhouse? The birds first appeared in
2007.DNA analysis of feathers suggested
a Finnish/Russian origin.Over 10 years,
23 clutches of eggs have been laid, with 11 chicks fledging: an average of 0.55
young per pair.The fledging rate was poor at first but is
increasing in recent years; the last 5 years average 0.8 and a remarkable 1.5
for the last 2 years.Detailed study of
the Cranes by site staff since they first appeared at Lakenheath, notably by
Norman Sills, has led to a good understanding of their requirements.Habitat management seeks to create ideal
conditions for both nesting and chick rearing.However, it is predation, mainly by Foxes that poses the major threat to
the youngsters.Habitat manipulation can
help with this but ultimately some control of Foxes is required.To ensure success, the latest technology of
trail cameras and thermal imagers is used in conjunction with a skilled
marksman.

The reedbed
management aims to create structural diversity for the benefit of the key
species.Cutting and grazing are the key
management tools and also aim to enhance viewing opportunities for
visitors.No airy-fairy stuff this – rather it is determined and targeted
conservation effort that brings results.Photo below - Dartmoor ponies eating reed and typha rhizomes

Wednesday, 2 November 2016

There have
been repeated nesting attempts by Black-winged Stilts in the UK in recent years.While spring influxes of stilts into Britain
have largely been driven by dry conditions in south-west Europe, at least part
of the most recent surge of records is also likely to have also been due to an
increase in the nearest breeding populations, particularly in northern France.
It is also clear that some individual stilts are now returning to Britain in
successive years. Although breeding attempts by stilts in Britain are no longer
just one-off events, their overall success has been poor and colonisation is by
no means assured. In 2016, we decided to
try to do something about this.This
blog covers the events of the year, with a fuller account being published in
British Birds in November 2016.

Following the failed breeding attempts by stilts in 2015, we decided to
be proactive and try to maximise the chances of successful breeding in 2016.But where should we focus our efforts given
that stilts could turn up anywhere? We agreed that Cliffe Pools was the obvious
site to work on, given that stilts had nested there in the two previous
years.Our plan was to develop a habitat
so good for Black-winged Stilts that we would draw them in from all
around.Little did we realize the impact
this would have!

The aim was to encourage stilts to nest in a location that contained not
only good chick-rearing habitat but that we could also protect from predation.
Foxes and Badgers are a known threat, but we also wanted to avoid a similar situation
to 2015 where stilts nested on islands where the chicks were predated by
Black-headed Gulls.So, beginning in
autumn 2015, management work started to try and encouraging stilts arriving in
spring 2016 onto a key pool.This
included cutting and grazing vegetation to turn it into prime stilt habitat,
installing a predator exclusion fence around the margins and manipulating water
levels to provide ideal feeding conditions as the likely time for stilt arrival
approached.We sat back and waited.

The first
stilt, a female, was recorded in Sussex on 12th April.The following day, she was on the pool at
Cliffe.A pair of stilts arrived on
17th and a fourth bird the following day.Two birds left on 19th April but three days later the remaining pair was
joined by a further four stilts – a male and three females.A pair were recorded at Manor Farm in Bucks
on 24th but relocated to Cliffe the following day.Stilts had been recorded at only three other
sites in Britain during April yet 8 or 9 birds had passed through or settled at
our pool at Cliffe!Photographs showed
that two of the males present, and which subsequently nested, had
near-identical head and neck markings to the two males that had nested nearby
in 2015.

Following a
delay during a period of cold weather, two pairs of stilts began nesting inside
the fenced area, with a third pair nesting on a lagoon outside out of it. The
first pair began incubating on 1st May. Based on plumage, the male is assumed
to be one of the males that nested at Cliffe in 2015.A wardening scheme was quickly organised as
soon as this first pair began nesting, and the frequency of Fox control was
increased. This pair diligently took
turns to defend the nest against a wide range of other bird species. As the
hatching date approached, the number of Black-headed Gulls feeding in the area
of the stilt nest began to increase. The gulls were feeding on chironomid
larvae, made more accessible by falling water levels, so we brought in a pump
to raise water levels slightly. This successfully reduced numbers of
Black-headed Gulls in the vicinity of the stilt nest, in the run up to
hatching.

The first
egg hatched on 25th May, and a second two days later. The adults successfully
defended the two chicks against potential avian threats before the effects of
bad weather intervened. At three days old, the youngest and smallest chick
succumbed during a period of torrential rain and cold winds. The first chick
continued to grow well, and became increasingly independent, frequently
exercising its wings.However, on 13th
June, about ten days from fledging, came another period of torrential rain,
this time overnight. Sadly, there was no sign of the chick the following
morning.

The second
pair began nesting on 3rd May, but failed five days after the start of
incubation, when rather bizarrely a male stilt was seen removing and dumping
the eggs from the nest. This pair then relocated across the Thames to South
Essex, a reserve where stilt habitat had been factored into the design and
stilts have turned up every year after the initial wetting-up.However, we were concerned about the
predation risk at this site and we waited to see where they would settle. After
much to-ing and fro-ing around the site, the stilts eventually settled to nest
on 31st May, on an island on Pitsea scrape. A poor choice! This scrape is close to a landfill site, and
consequently surrounded by high densities of Foxes and large gulls. The
reedbeds surrounding the scrape meant it was impossible to install a temporary predator
exclusion fence.A wardening post to
watch over the stilts was again immediately arranged, but the nest failed five
days later. Frustation!

The third
pair started nesting on 14th May but unfortunately just outside the
fenced area.Both birds would chase off
any potential avian predators, including even quite distant Marsh Harriers,
commuting back and forth over the site, and posing no obvious threat.
Consequently, the eggs were frequently left unguarded. The pair lost their eggs
on the night of the 17th May.Although
the cause was uncertain, a Fox was seen close to the predated nest the
following day.

This pair
subsequently reappeared in north Kent, where they were first seen at Higham
Marshes on 7th or 8th June and began nesting there on 11th June. The nest was
in an area where Fox control was already being carried out, and where other
waders had enjoyed a successful breeding season. We again organised wardening
of this pair. The incubation period proceeded uneventfully until, on 4th July, just
before the eggs were expected to hatch, all four eggs were predated by Carrion
Crows.

As
discussed above, the establishment of Black-winged Stilt as a regular breeding
species in Britain is by no means assured, despite the projected changes in
climate. In particular, there are very
few ideal breeding areas in Britain – areas that have appropriate feeding and
nesting habitat, and where predation levels are sufficiently low for stilts to
fledge young. The key measures to
increase the breeding success of pioneering pairs should involve:

creation
and management of ideal feeding and nesting habitat,

management
of water levels to provide optimum feeding and nest protection,

minimising
nest predation, particularly by Foxes, through the provision of predator-exclusion
fencing or by lethal control, and

preventing
disturbance by humans, and the theft of eggs, by rapidly implementing wardening
schemes.

The RSPB reserve
teams in North Kent and South Essex, together with our contracted wardens,
worked supremely hard to try to deliver stilt success in 2016. Despite what may
seem as a failure with the loss of all five nesting attempts, we have all
learnt a huge amount about how to manage for this colonizing species and this
will no doubt tip the balance fully towards success in future years.Plans are already afoot for 2017!

A grizzled old ecologist/birder, usually to be found roaming around the Lee Valley and occasionally further afield. Fortunate to be involved in the management of some of the UK's finest nature reserves and always looking for ways of improving them for birds.